Aquathol Super K controls submerged weeds such as Hydrilla, Eurasian Water Milfoil and Curly Leaf Pondweed without harming other beneficial species such as Vallisneria, Water Stargrass, Chara, and Nitella. Does not affect beneficial emerged plants such as Spadderdock, Water Lilies, Pickerelweed, and Bulrushes, which are considered to be valuable in a sound aquatic habitat. The short residual contact time (12-48 hrs) makes it effective in still or slow moving water in canals, ponds and lakes. Effective: Control of Hydrilla, Eurasian Water Milfoil, Curly Leaf Pondweed and other submerged nuisance plants.